S6 Linncean Society, 



portant, which regards the geographical distribution of animals, Mr. 

 Ogilby regarded the native dog as an importation, probably contem- 

 porary with the original settlement of the inhabitants, and adduced 

 various arguments in support of this opinion. It followed that the 

 remaining exceptions to the purely marsupial character of Australian 

 mammalogy belong exclusively to the Rodent type, a fact as singu- 

 lar, and scarcely less important than that to which it forms an ex- 

 ception. 



Mr. Ogilby afterwards proceeded to the description of two new 

 species of Australian Rodents, belonging to forms altogether new, or 

 hitherto not known to exist in that country ; and expressed his belief 

 that more extensive research would lead to many more discoveries 

 of a similar nature, and tend to diminish the disproportion which at 

 present exists between the members of marsupial and non-marsupial 

 species. The first of the new forms described by Mr. Ogilby formed 

 the type of a new genus, for which he proposed the name of Coni- 

 lurus, in allusion to its external resemblance to a small rabbit with 

 a long tail. The specimens had been originally sent from Sydney 

 by the late Mr. George Coley, under the name of the "native rabbit," 

 and have been long deposited in the Museum of the Linnsean Society. 

 The animal seems to have disappeared from the settled parts of New 

 South Wales since that period, but was found in abundance on 

 the banks of the river Darling, during the late expedition of Ma- 

 jor Mitchell, from whose forthcoming journal an interesting ex- 

 tract was read, descriptive of its habits and oeconomy. Major Mit- 

 chell's party had frequently encountered large piles of small branches 

 and brushwood, of a size sufficient to fill two or three large carts, so 

 ingeniously and compactly woven together, that it was impossible to 

 remove a part without removing the whole fabric. At first they sup- 

 posed these piles to be collected by the natives for the purpose of 

 making signal fires, but the regularity and compactness of their tex- 

 ture led to a closer examination, and on being broken open, it was 

 discovered that they were entirely the work of the little animal in 

 question, whose instinct thus prompts it to erect a fortress against 

 the attacks of the native dog. 



The other animal described by Mr. Ogilby, though not belonging 

 to a new genus, was equally interesting, as illustrative of the laws of 

 the geographical distribution of animals. It was a true GeYhoR{Dipus) 

 from the central plains of New Holland, and had been found by 

 MajorMitchellnear the junction of the Murray and the Morrumbidgee. 

 It is distinguished from the Gerboas of Asia and Africa by having 

 only four toes on the hind feet, namely three normal toes and a 

 smaller one about one third of its distance up the metatarsus, on the 

 inner side. Mr. Ogilby proposed to dedicate this curious animal to 

 its discoverer, and to commemorate the circumstance by the name 

 of Dipus MitCfieUii. 



Dec. 19. — Mr. Ward, F.L.S., exhibited a series of specimens of 

 Laminaria digitata (Fucus digitatuSf L.) showing the curious mode 

 by which the species of that genus renovate their fronds. These spe- 

 cimens Mr. Ward had received from Mrs. Griffiths, by whom they 



